1. Field of the Invention
The invention relates to radio frequency identification (RFID) systems, and in particular, to harvesting energy in an RFID systems environment.
2. Background Art
Radio frequency identification (RFID) tags are electronic devices that may be affixed to items whose presence is to be detected and/or monitored. The presence of an RFID tag, and therefore the presence of the item to which the tag is affixed, may be checked and monitored wirelessly by devices known as “readers.” Readers typically have one or more antennas transmitting radio frequency signals to which tags respond. Because the reader “interrogates” RFID tags, and receives signals back from the tags in response to the interrogation, the reader is sometimes termed a “reader interrogator” or simply “interrogator.”
With the maturation of RFID technology, efficient communication between tags and interrogators has become a key enabler in supply chain management, especially in manufacturing, shipping, and retail industries, as well as in building security installations, healthcare facilities, libraries, airports, warehouses etc.
With the increased use of peripheral devices in RFID systems, it is becoming increasingly important to devise new ways to provide power to such devices. For example, a mobile computer with an integrated RFID interrogator may be used by an operator wearing a headset to communicate with the computer or a central communications point. A reader interrogator may be remote from a conventional power source, etc.
Thus, what is needed are improved ways of providing power to various devices included in RFID systems.